Characterization and Control of Structure, Energetics and Electrical Properties at Interfaces between Perovskite Active Layers and Charge-Collection Electrodes

钙钛矿活性层和电荷收集电极之间界面的结构、能量和电性能的表征和控制

• 批准号: 1506504
• 负责人: Neal Armstrong
• 金额: $ 30万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1506504&HistoricalAwards=false
• 关键词: Characterization; Control; Structure; Energetics; Electrical

Nontechnical Description: This project focuses on the characterization and control of the interfaces formed between electrodes and new materials (perovskites) that have shown great promise as active layers in new solar cell platforms. Such platforms have potential as inexpensive, earth-abundant alternatives for production of electricity from sunlight. One of the key challenges in the development of new energy conversion platforms is the understanding and optimization of the transfer of electrical charges between the active layer material and the electrical contacts. This project develops new measurement approaches in order to understand the structure of the active layer near the electrical contact, and how this structure influences electrical properties that ultimately control energy conversion efficiency. The project also provides opportunities for training of graduate students at the University of Arizona and for undergraduate students from the AZ Science, Engineering, and Math Scholars (ASEMS) Program, which focuses on students from minority populations, low-income households, and families where the student is the first to attend college. The co-principal investigators also continue a partnership with Yavapai Community College in Prescott, Arizona - providing "gateway" research experiences for freshman and sophomores.Technical Description: This project focuses on the nanometer-scale characterization and control of physical, energetic and electrical property heterogeneity, across interfaces between metal halide perovskites, as well as hybrid active layer materials, and electrical contacts. These interfaces are model systems to explore charge collection or injection in emerging thin-film solar energy conversion platforms. The project includes: a) control of interface composition in prototype electrical contacts and charge selective interlayers, using self-assembled monolayers with terminal functional groups that "template" growth of perovskite active layers; b) characterization of valence band energies and energetic dispersion as a function of active layer structure via high-sensitivity UV-photoemission spectroscopies and high-resolution, angle-resolved X-ray photoemission; c) probing conduction band energies in the active layer and dispersion in band edge energies arising from compositional and structural heterogeneity, using waveguide-based spectroelectrochemical techniques; d) characterization of the electrical properties of contact/active layer heterojunctions at 10-100 nm length scales using conducting-tip atomic force microscopy to map heterogeneity in electrical properties. This fundamental study could reveal the charge transfer mechanisms and ultimately lead to efficient energy conversion in the emerging solar cell platforms.

非技术描述：该项目的重点是电极和新材料（钙钛矿）之间形成的界面的表征和控制，这些材料在新的太阳能电池平台中作为活性层显示出巨大的前景。这种平台有潜力成为廉价的、地球资源丰富的太阳能发电替代品。开发新能源转换平台的关键挑战之一是理解和优化活性层材料和电触点之间的电荷转移。该项目开发了新的测量方法，以了解电接触附近有源层的结构，以及这种结构如何影响最终控制能量转换效率的电气特性。该项目还为亚利桑那大学的研究生和亚利桑那州科学，工程和数学学者（ASEMS）计划的本科生提供培训机会，该计划侧重于少数民族，低收入家庭和家庭的学生。共同主要研究人员还继续与亚利桑那州普雷斯科特的Yavapai社区学院合作-为新生和大学生提供“门户”研究经验。技术描述：该项目侧重于纳米尺度的表征和控制物理，能量和电学性质的异质性，跨金属卤化物钙钛矿之间的界面，以及混合活性层材料，和电接触。这些接口是探索新兴薄膜太阳能转换平台中的电荷收集或注入的模型系统。该项目包括：B）通过高灵敏度UV-光电子能谱和高分辨率角分辨X-射线光电子能谱表征作为活性层结构的函数的价带能量和能量色散; c）使用基于波导的光谱电化学技术探测活性层中的导带能量和由组成和结构不均匀性引起的带边能量的分散; d）使用导电材料表征10-100 nm长度尺度下的接触/有源层异质结的电性质，尖端原子力显微镜来绘制电学特性的异质性。这项基础研究可以揭示电荷转移机制，并最终导致新兴太阳能电池平台的有效能量转换。